MV - monetary value.
Youth takes 24 to 28 day cycle.
Always build and improve facilities but be careful, DO NOT build while a cycle is in progress (ie youth, medical, training boosters etc). If you interrupt the cycle it reverts to day 1 and you lose out. Let the cycle compete then improve/build. You need to build all over to grow the club in terms of supporter base, income, booster packs.

I try to keep a reserve spot for guests, to buy Free Trs and sell on.